diff --git a/keystone/catalog/controllers.py b/keystone/catalog/controllers.py
index 8dddf46936..b0b2d934b2 100644
--- a/keystone/catalog/controllers.py
+++ b/keystone/catalog/controllers.py
@@ -86,8 +86,10 @@ class Endpoint(controller.V2Controller):
 
         legacy_endpoint_ref = endpoint.copy()
 
+        # pop all urls off the endpoint so we don't persist them more than once
         urls = dict((i, endpoint.pop('%surl' % i)) for i in INTERFACES
                     if endpoint.get('%surl' % i) is not None)
+
         legacy_endpoint_id = uuid.uuid4().hex
         for interface, url in urls.iteritems():
             endpoint_ref = endpoint.copy()